In the art of slide fasteners or zippers, it has long been desirable to make the slide fastener water proof or water resistant. Some solutions were directed to making the zipper structure itself water impervious. Other solutions relied on forming an interlocking fit with ancillary material directly adjacent the zipper so that the ancillary material would form a barrier between the environment and the zipper. An example of the later can be found in U.S. Pat. No. 3,490,109 (the '109 patent).
In the '109 patent, the means for providing a sealing closure was effectuated by integrating coupling members or zipper teeth in an elastic sealing strip located above the outer portion of the teeth so that when the teeth were meshed during closure, the sealing strip would likewise form an interlock in a tongue and groove manner. This solution, however, required the custom manufacture of specialty zippers since the teeth were integral with the sealing strip. Consequently, while providing a seal, the costs of manufacture were comparatively high to those of conventional zippers.
Another solution proposed by the prior art and exemplified in U.S. Pat. No. 3,624,871 (the '871 patent) provided for highly overlapped zipper flaps that extended over the outer zipper structure. While this structure provided a low cost solution to the challenge, the deficiency of this design, however, was the structure's failure to provide some positive means for maintaining the overlap.
In view of the foregoing, it is apparent that a need exists for a simple and low cost means for providing a water resistant slide fastener, or an outer closure structure for use with conventional slide fasteners. The present invention is intended to meet these needs and is directed to the later.